Manually default Error messages to avoid dart2js code bloat.

sdk/lib/core/errors.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of dart.core;
 
 /**
  * Error objects thrown in the case of a program failure.
  *
  * An `Error` object represents a program failure that the programmer
@@ skipping 225 matching lines @@
 
   // TODO(lrn): This constructor should be called only with string values.
   // It currently isn't in all cases.
   /**
    * Create a new [RangeError] with the given [message].
    */
   RangeError(var message)
       : invalidValue = null, start = null, end = null, super(message);
 
   /** Create a new [RangeError] with a message for the given [value]. */
-  RangeError.value(num value, [String message = "Value not in range"])
+  RangeError.value(num value, [String message])
       : invalidValue = value, start = null, end = null,
-        super(message);
+        super(message != null ? message : "Value not in range");
 
   /**
    * Create a new [RangeError] with for an invalid value being outside a range.
    *
    * The allowed range is from [start] to [end], inclusive.
    * If `start` or `end` are `null`, the range is infinite in that direction.
    *
    * For a range from 0 to the length of something, end exclusive, use
    * [RangeError.index].
    */
-  RangeError.range(this.invalidValue, this.start, this.end,
-                   [String message = "Invalid value"]) : super(message);
+  RangeError.range(this.invalidValue, this.start, this.end, [String message])
+      : super(message != null ? message : "Invalid value");
 
   /**
    * Creates a new [RangeError] stating that [index] is not a valid index
    * into [indexable].
    *
    * The [length] is the length of [indexable] at the time of the error.
    * If `length` is omitted, it defaults to `indexable.length`.
    *
    * The message is used as part of the string representation of the error.
    */
@@ skipping 39 matching lines @@
 
   /**
    * Creates a new [IndexError] stating that [invalidValue] is not a valid index
    * into [indexable].
    *
    * The [length] is the length of [indexable] at the time of the error.
    * If `length` is omitted, it defaults to `indexable.length`.
    *
    * The message is used as part of the string representation of the error.
    */
-  IndexError(this.invalidValue, indexable,
-             [String message = "Index out of range", int length])
+  IndexError(this.invalidValue, indexable, [String message, int length])
       : this.indexable = indexable,
         this.length = (length != null) ? length : indexable.length,
-        super(message);
+        super(message != null ? message : "Index out of range");
 
   // Getters inherited from RangeError.
   int get start => 0;
   int get end => length - 1;
 
   String toString() {
     String target = Error.safeToString(indexable);
     if (invalidValue < 0) {
       return "RangeError: $message ($target[$invalidValue]): "
              "index must not be negative.";
@@ skipping 164 matching lines @@
  * the first time it is read. If evaluating the initializer expression causes
  * another read of the variable, this error is thrown.
  */
 class CyclicInitializationError extends Error {
   final String variableName;
   CyclicInitializationError([this.variableName]);
   String toString() => variableName == null
       ? "Reading static variable during its initialization"
       : "Reading static variable '$variableName' during its initialization";
 }